POTTERS H (2020) Remarkable winter concentrations of Blue Tits Cyanistes caeruleus in Golden Larch Larix kaempferi plots. LIMOSA 93 (2): 89-91.

After huge numbers of migrating Blue Tits had been recorded in autumn 2019 in the Netherlands, the species remained exceptionally abundant in the following months. Early January 2020 several flocks of 30-130 birds were seen in the western part of the Dutch province of Noord-Brabant. The largest flock comprised of 320 individuals. No other species accompanied these Blue Tits. Flocks were mainly or exclusively seen foraging in Golden Larch stands. These relatively dense stands (mean distances between trees 5-10 m) of at least 15 m high larches measured 0.7-3.2 ha. Blue Tits foraged on branches and twigs; the cones were almost completely ignored. While foraging the Blue Tits behaved very actively high in the trees. It remained unknown what type of food the tits were feeding on, presumably as food items were very small. When visiting the same locations later in January, flocks were much smaller, as was also noted in other parts of the country. This decrease could be due to depletion of the food source and/or return migration to breeding sites.

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